CERAMIC MICROSTRUCTURE AND OXYGEN PERMEABILITY OF SRCO(FE,M)O3-DELTA (M = CU OR CR) PEROVSKITE MEMBRANES

Stabilization of the cubic perovskite phase was demonstrated in the Sr Co0.90-xFe0.10CrxO3-delta oxide system at x greater than or equal to 0 .03. Oxygen permeability of SrCo(Fe, Cr)O3-delta solid solutions was i ndependent of chromium content at x = 0.01-0.05. It was found that red ucing ceramic grain size dimensions resulted in decreasing thermal exp ansion electrical conductivity, and oxygen permeability of SrCo(Fe, Cu )O3-delta ceramic membranes. Oxygen transport through SrCo(Fe, M)O3-de lta ceramics was shown to be limited by both the bulk ionic conductivi ty and oxygen exchange currents. The limiting effect of the membrane p ermeate-side surface on the permeation was higher in comparison with t hat on the feed-side surface.